David W Clow (Former Employee)
Science and Products
Filter Total Items: 67
Old groundwater influence on stream hydrochemistry and catchment response times in a small Sierra Nevada catchment: Sagehen Creek, California
The relationship between the chemical and isotopic composition of groundwater and residence times was used to understand the temporal variability in stream hydrochemistry in Sagehen basin, California. On the basis of the relationship between groundwater age and [Ca2+], the mean residence time of groundwater feeding Sagehen Creek during base flow is approximately 28 years. [Cl−]:[Ca2+] ratios in Sa
Authors
Laura K. Rademacher, Jordan F. Clark, David W. Clow, Hudson G. Bryant
The U.S. Geological Survey Hydrologic Benchmark Network
No abstract available.
Authors
Peter S. Murdoch, Michael R. McHale, M. Alisa Mast, David W. Clow
Rocky Mountain Snowpack Chemistry at Selected Sites, 2002
During spring 2002, the chemical composition of annual snowpacks in the Rocky Mountain region of the Western United States was analyzed. Snow samples were collected at 75 geographically distributed sites extending from New Mexico to Montana. Near the end of the 2002 snowfall season, the snow-water equivalent (SWE) in annual snowpacks sampled generally was below average in most of the region. Regio
Authors
George P. Ingersoll, M. Alisa Mast, Leora Nanus, David J. Manthorne, David W. Clow, Heather M. Handran, Jesse A. Winterringer, Donald H. Campbell
Rocky Mountain snowpack chemistry at selected sites for 2001
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants in a netw
Authors
George P. Ingersoll, M. Alisa Mast, David W. Clow, Leora Nanus, Donald H. Campbell, Heather Handran
Evidence for nutrient enrichment of high-elevation lakes in the Sierra Nevada, California
Long-term measurements (1983-2001) of nutrients and seston in Emerald Lake (Sierra Nevada, California) have revealed ecologically significant patterns. Nitrate, both during spring runoff and during growing seasons, declined from 1983 through 1995. Declining snowmelt nitrate was caused primarily by changes in snow regime induced by the 1987-1992 drought: years with shallow, early melting snowpacks
Authors
James O. Sickman, John M. Melack, David W. Clow
Changes in the chemistry of lakes and precipitation in high-elevation national parks in the western United States, 1985–1999
High-elevation lakes in the western United States are sensitive to atmospheric deposition of sulfur and nitrogen due to fast hydrologic flushing rates, short growing seasons, an abundance of exposed bedrock, and a lack of well-developed soils. This sensitivity is reflected in the dilute chemistry of the lakes, which was documented in the U.S. Environmental Protection Agency's Western Lake Survey o
Authors
David W. Clow, James O. Sickman, Robert G. Striegl, David P. Krabbenhoft, John G. Elliott, Mark M. Dornblaser, David A. Roth, Donald H. Campbell
Chemistry of selected high-elevation lakes in seven national parks in the western United States
A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky Mountain Nationa
Authors
David W. Clow, Robert G. Striegl, Leora Nanus, M. Alisa Mast, Donald H. Campbell, David P. Krabbenhoft
Rocky Mountain snowpack chemistry network: History, methods, and the importance of monitoring mountain ecosystems
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey to more thoroughly determine the quality of precipitation and to identify sources of atmospherically deposited pollution in a network of high-elevation sites. Depth-integrated samples of seasonal snowpacks at 52 sampling sites, in a network from New Mexico to M
Authors
George P. Ingersoll, John T. Turk, M. Alisa Mast, David W. Clow, Donald H. Campbell, Zelda C. Bailey
Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition
Depth-integrated snowpack chemistry was measured just prior to maximum snowpack depth during the winters of 1992-1999 at 12 sites co-located with National Atmospheric Deposition Program/National Trend Network (NADP/NTN) sites in the central and southern Rocky Mountains, USA. Winter volume-weighted mean wet-deposition concentrations were calculated for the NADP/NTN sites, and the data were compared
Authors
David W. Clow, George P. Ingersoll, M. Alisa Mast, John T. Turk, Donald H. Campbell
Mercury loading and methylmercury production and cycling in high-altitude lakes from the Western United States
Studies worldwide have shown that mercury (Hg) is a ubiquitous contaminant, reaching even the most remote environments such as high-altitude lakes via atmospheric pathways. However, very few studies have been conducted to assess Hg contamination levels of these systems. We sampled 90 mid-latitude, high-altitude lakes from seven national parks in the western United States during a four-week period
Authors
David P. Krabbenhoft, Mark L. Olson, John F. DeWild, David W. Clow, Robert G. Striegl, Mark M. Dornblaser, Peter C. Van Metre
Environmental characteristics and water quality of hydrologic benchmark network stations in the western United States, 1963-95
This report describes the environmental characteristics and water-quality characteristics of 12 hydrologic benchmark network streams in the Western United States. This information was compiled to aide in the interpretation and application of water-quality data collected as part of the Hydrologic Benchmark Network Program.
Authors
M. Alisa Mast, David W. Clow
Timescales for migration of atmospherically derived sulphate through an alpine/subalpine watershed, Loch Vale, Colorado
Sulphur 35, a cosmogenically produced radioisotope with a short half‐life (87 days), was measured in snowpack during 1993–1997 and at four locations within the Loch Vale watershed during 1995–1997. The four sites include the two main drainages in the watershed, Andrews Creek and Icy Brook, a small south facing catchment flowing into Andrews Creek (Andrews Spring 1), and a similar north facing catc
Authors
Robert L. Michel, Donald H. Campbell, David W. Clow, John T. Turk
Science and Products
Filter Total Items: 67
Old groundwater influence on stream hydrochemistry and catchment response times in a small Sierra Nevada catchment: Sagehen Creek, California
The relationship between the chemical and isotopic composition of groundwater and residence times was used to understand the temporal variability in stream hydrochemistry in Sagehen basin, California. On the basis of the relationship between groundwater age and [Ca2+], the mean residence time of groundwater feeding Sagehen Creek during base flow is approximately 28 years. [Cl−]:[Ca2+] ratios in Sa
Authors
Laura K. Rademacher, Jordan F. Clark, David W. Clow, Hudson G. Bryant
The U.S. Geological Survey Hydrologic Benchmark Network
No abstract available.
Authors
Peter S. Murdoch, Michael R. McHale, M. Alisa Mast, David W. Clow
Rocky Mountain Snowpack Chemistry at Selected Sites, 2002
During spring 2002, the chemical composition of annual snowpacks in the Rocky Mountain region of the Western United States was analyzed. Snow samples were collected at 75 geographically distributed sites extending from New Mexico to Montana. Near the end of the 2002 snowfall season, the snow-water equivalent (SWE) in annual snowpacks sampled generally was below average in most of the region. Regio
Authors
George P. Ingersoll, M. Alisa Mast, Leora Nanus, David J. Manthorne, David W. Clow, Heather M. Handran, Jesse A. Winterringer, Donald H. Campbell
Rocky Mountain snowpack chemistry at selected sites for 2001
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey, in cooperation with the National Park Service, U.S. Department of Agriculture Forest Service, and other agencies, to more thoroughly determine the chemical composition of precipitation and to identify sources of atmospherically deposited contaminants in a netw
Authors
George P. Ingersoll, M. Alisa Mast, David W. Clow, Leora Nanus, Donald H. Campbell, Heather Handran
Evidence for nutrient enrichment of high-elevation lakes in the Sierra Nevada, California
Long-term measurements (1983-2001) of nutrients and seston in Emerald Lake (Sierra Nevada, California) have revealed ecologically significant patterns. Nitrate, both during spring runoff and during growing seasons, declined from 1983 through 1995. Declining snowmelt nitrate was caused primarily by changes in snow regime induced by the 1987-1992 drought: years with shallow, early melting snowpacks
Authors
James O. Sickman, John M. Melack, David W. Clow
Changes in the chemistry of lakes and precipitation in high-elevation national parks in the western United States, 1985–1999
High-elevation lakes in the western United States are sensitive to atmospheric deposition of sulfur and nitrogen due to fast hydrologic flushing rates, short growing seasons, an abundance of exposed bedrock, and a lack of well-developed soils. This sensitivity is reflected in the dilute chemistry of the lakes, which was documented in the U.S. Environmental Protection Agency's Western Lake Survey o
Authors
David W. Clow, James O. Sickman, Robert G. Striegl, David P. Krabbenhoft, John G. Elliott, Mark M. Dornblaser, David A. Roth, Donald H. Campbell
Chemistry of selected high-elevation lakes in seven national parks in the western United States
A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky Mountain Nationa
Authors
David W. Clow, Robert G. Striegl, Leora Nanus, M. Alisa Mast, Donald H. Campbell, David P. Krabbenhoft
Rocky Mountain snowpack chemistry network: History, methods, and the importance of monitoring mountain ecosystems
Because regional-scale atmospheric deposition data in the Rocky Mountains are sparse, a program was designed by the U.S. Geological Survey to more thoroughly determine the quality of precipitation and to identify sources of atmospherically deposited pollution in a network of high-elevation sites. Depth-integrated samples of seasonal snowpacks at 52 sampling sites, in a network from New Mexico to M
Authors
George P. Ingersoll, John T. Turk, M. Alisa Mast, David W. Clow, Donald H. Campbell, Zelda C. Bailey
Comparison of snowpack and winter wet-deposition chemistry in the Rocky Mountains, USA: Implications for winter dry deposition
Depth-integrated snowpack chemistry was measured just prior to maximum snowpack depth during the winters of 1992-1999 at 12 sites co-located with National Atmospheric Deposition Program/National Trend Network (NADP/NTN) sites in the central and southern Rocky Mountains, USA. Winter volume-weighted mean wet-deposition concentrations were calculated for the NADP/NTN sites, and the data were compared
Authors
David W. Clow, George P. Ingersoll, M. Alisa Mast, John T. Turk, Donald H. Campbell
Mercury loading and methylmercury production and cycling in high-altitude lakes from the Western United States
Studies worldwide have shown that mercury (Hg) is a ubiquitous contaminant, reaching even the most remote environments such as high-altitude lakes via atmospheric pathways. However, very few studies have been conducted to assess Hg contamination levels of these systems. We sampled 90 mid-latitude, high-altitude lakes from seven national parks in the western United States during a four-week period
Authors
David P. Krabbenhoft, Mark L. Olson, John F. DeWild, David W. Clow, Robert G. Striegl, Mark M. Dornblaser, Peter C. Van Metre
Environmental characteristics and water quality of hydrologic benchmark network stations in the western United States, 1963-95
This report describes the environmental characteristics and water-quality characteristics of 12 hydrologic benchmark network streams in the Western United States. This information was compiled to aide in the interpretation and application of water-quality data collected as part of the Hydrologic Benchmark Network Program.
Authors
M. Alisa Mast, David W. Clow
Timescales for migration of atmospherically derived sulphate through an alpine/subalpine watershed, Loch Vale, Colorado
Sulphur 35, a cosmogenically produced radioisotope with a short half‐life (87 days), was measured in snowpack during 1993–1997 and at four locations within the Loch Vale watershed during 1995–1997. The four sites include the two main drainages in the watershed, Andrews Creek and Icy Brook, a small south facing catchment flowing into Andrews Creek (Andrews Spring 1), and a similar north facing catc
Authors
Robert L. Michel, Donald H. Campbell, David W. Clow, John T. Turk